CF803F.Coprime Subsequences

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题目描述

Let's call a non-empty sequence of positive integers a1,a2... aka_{1},a_{2}...\ a_{k} coprime if the greatest common divisor of all elements of this sequence is equal to 11 .

Given an array aa consisting of nn positive integers, find the number of its coprime subsequences. Since the answer may be very large, print it modulo 109+710^{9}+7 .

Note that two subsequences are considered different if chosen indices are different. For example, in the array [1,1][1,1] there are 33 different subsequences: [1][1] , [1][1] and [1,1][1,1] .

输入格式

The first line contains one integer number nn ( 1<=n<=1000001<=n<=100000 ).

The second line contains nn integer numbers a1,a2... ana_{1},a_{2}...\ a_{n} ( 1<=ai<=1000001<=a_{i}<=100000 ).

输出格式

Print the number of coprime subsequences of aa modulo 109+710^{9}+7 .

输入输出样例

  • 输入#1

    3
    1 2 3
    

    输出#1

    5
    
  • 输入#2

    4
    1 1 1 1
    

    输出#2

    15
    
  • 输入#3

    7
    1 3 5 15 3 105 35
    

    输出#3

    100
    

说明/提示

In the first example coprime subsequences are:

  1. 11
  2. 1,21,2
  3. 1,31,3
  4. 1,2,31,2,3
  5. 2,32,3

In the second example all subsequences are coprime.

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